1. Field of the Invention
The present invention relates generally to cryolytic treatment of obstructive sleep apnea.
2. Description of Related Art
Obstructive sleep apnea (OSA) is disease that affects up to 20% of the adult population. OSA generally occurs during sleep when soft tissue obstructs the airway and creates cessation of, or impedes, breathing. Obstruction can occur at one or more levels including the retropalatal and retrolingual areas. Surgical correction of such obstructions remains a challenge, specifically for the retrolingual area. Removal or ablation of tongue tissue has been utilized with poor results due to complications, such as severe bleeding, abscess formation, and/or the inability to move the tongue anterior enough to relieve the obstruction.
It is known that patients with OSA have a higher percentage of adipose deposits in the areas of obstruction, specifically, the soft palate and uvula, base of tongue and lateral pharyngeal walls. The adipose tissue may be up to or greater than 40% of the total volume of tissues in these areas. Removal of the fat deposits in these areas would permit relief from OSA symptoms while preserving surrounding tissue. To date, however, cryolytic treatment of OSA has involved procedures analogous to ablation, merely substituting cryolytic cold for electrolytic heat and nonselectively destroying tissue in a similar manner—and with the same complications.